The TPA vote was always going to be close, and the Senate voted to cut off debate by 60-37 — the bare minimum to advance.

The 2-vote margin of error from last month when the Senate last approved the measure was cut in half Tuesday morning, as Sen. Ted Cruz, R-Texas, announced his opposition to TPA unless Republican leaders commit to killing the Export-Import Bank. Senate Advances Trade Promotion Authority

For the past few days, the vote had been billed as a matter of trust between Republican leadership and pro-trade Democrats, who worried a vote on the "fast-track" measure would not be followed by a vote on the extension of a worker assistance program known as Trade Adjustment Assistance.

Most of the pro-trade Democrats stuck with the president.

https://twitter.com/StevenTDennis/status/613386005220093952

The Senate must still vote on final passage of Trade Promotion Authority, as well as other pieces of the trade agenda.

The trade agenda has already been bedeviled by multiple "procedural snafus" in the parlance of White House Press Secretary Josh Earnest, but the White House has expressed confidence repeatedly that it will ultimately succeed.

While Senate Majority Leader Mitch McConnell, R-Ky., has repeatedly said a vote on TAA would immediately follow the TPA vote, with the hope that both would be sent to Obama by next week's recess, Speaker John A. Boehner, R-Ohio, issued a statement Tuesday to assure pro-trade Democrats he had their backs as well.

"We remain committed to ensuring that both TPA and TAA are passed and enacted into law," Boehner said in a statement. "The House has passed TPA as a standalone measure. The House will consider TAA once it passes the Senate as part of a new trade preferences bill. And we are ready to go to conference on the customs bill. Our goal is to get TPA and TAA to the president's desk this week and deliver this win for the American people."